As the number of electric vehicles and vehicles with an electric drive increases, the necessity of designing a charging infrastructure for vehicles of this kind increases. This means that publicly accessible charging parks, in particular having quick-charging stations located therein, have to be provided along roads with a particularly high level of traffic. In particular, planning of a quick-charging infrastructure and of what are known as HPC (High Power Charging) charging parks that are to be provided in this case makes it, possible to drastically reduce charging operations that are to be performed at the charging columns. For this purpose, however, it is necessary that a connection by means of a medium-voltage grid is designed for more than 150 kW per charging point or charging station. There is provision for the quick-charging stations to be equipped with 150 to 350 kW or more. In HPC charging parks, a connection by means of a medium-voltage grid is generally necessary in this case even from two charging points or charging stations. For a connection having such high powers that are to be provided, an operator of the respective HPC charging park requires a corresponding grid connection having a power in the range of a few MVA. In the case of quick DC charging, charging currents of up to 500 A DC are demanded. As a result, electric vehicles can be charged in a few minutes. This means that the aim is to minimize the charging times through increased power transmission, wherein the increased power transmission does not, however, have to be provided by the respective charging park operator alone but instead also by the operator of the respective medium-voltage grid. However, even today the free availability of powers in many medium-voltage grids is greatly restricted. In this case, a respective grid operator of a respective medium-voltage grid always plans with a static permanent load in the case of a granting of network accesses. An operator of a charging infrastructure or of a charging park has to pay what is known as a demand rate annually for providing power through the network operator of the respective medium-voltage grid that supplies power thereto. In Europe, said demand rate is currently on average around 80 EUR/kVA. The annual fees for HPC charging parks, that is to say for charging parks having quick-charging points, which in each case are intended to provide a power of 350 kW or more, are enormous as a result.
To reduce the grid connection costs that therefore arise, quick-charging parks are designed, for example, with what is known as a simultaneity factor. In this case, it is assumed that a full power is never demanded at the same time at charging points of the respective charging park by vehicles connected to said charging points. In general, a charging electronics system that is to be provided in the charging park or at the charging points is in this case also implemented with a corresponding simultaneity factor. Nevertheless, if, in a given case, a full power should be required at all of the charging points, the respective charging operations to be performed at the individual charging points are limited and a corresponding charging time of the individual vehicles connected to said charging points is increased accordingly.
US 2014/0089016, which is incorporated by reference herein, discloses a centralized, server-based system and a method for managing and reserving parking spaces that are capable of charging an electric vehicle. The described system handles sets of parking spaces as exchangeable, pooled resources so that a user of an electric vehicle can book a parking reservation with requirements by virtue of said user specifying the parking at a desired location. The parking spaces provided serve selectively only for parking or for charging. The parking spaces are in this case operated as a common parking area and each space has equal access to a charging station. The server comprised by the system determines the availability of the charging capacity within a parking time window and the user of a respective vehicle can select a parking time up to the maximum charging time that is required to charge the electric vehicle.
Against the background of the prior art, described hereinafter is a charging infrastructure that makes it possible to temporarily provide an increased power demand for charging electric vehicles in a manner that is optimized in terms of operating costs.